碳纳米管纤维导热性能的实验研究

Experimental study on thermal conductivity of carbon nanotube fiber

中文关键词: 碳纳米管纤维  导热性能  瞬态电热技术  电流加热

英文关键词: carbon nanotube fiber  thermal properties  the transient electro-thermal technique  current heating

中文摘要:

      利用瞬态电热技术对碳纳米管纤维（CNTF）的导热性能进行测量，研究了不同加热电流下CNTF导热性能的变化规律。在测量过程中，发现热扩散系数存在“突变”现象，CNTF的高热扩散系数比低热扩散系数大约提高1.65-3.85倍，随着电流的增加，热扩散系数呈下降趋势。对电流加热过程中的声子散射机制进行了分析总结，并探究了CNTF中微观结构演变。研究表明，热扩散系数下降主要是由于高温加热过程中，倒逆声子散射增强和组成CNTF中的多壁碳纳米管结构变化造成。

英文摘要:

      The thermal properties of carbon nanotube fiber (CNTF) are measured by using the transient electro-thermal technique, and the variations of thermal diffusivity of CNTF under different heating currents are studied. During the process, a "sudden jump" is found in the thermal diffusivity. The high-level thermal diffusivity of CNTF is about 1.65-3.85 times higher than the lower one, and the thermal diffusivity shows a decreasing trend with the increase of the annealing current. The mechanism of scattering during this progress is analyzed, and the microstructure alterations of CNTF is explored. The results show that the enhancement of Umklapp scattering and the structural modification of multi-wall carbon nanotubes inside CNTF cause the thermal diffusivity decreases.